Pulverizer



Nov. 19, 1929. H WARING 1,735,985

PULVERI ZER Filed Sept. 6, 1927 Patented Nov. 19, 1929 UNITED STATESPATENT OFFICE HORACE WARING, OF LIVERPOOL, ENGLAND, ASSIGNOR TOASSOCIATED LEAD 'MANU- FACTURERS LIMITED, OF LONDON, ENGLAND, A. BRITISHPULVERIZEB Application led September 0, 1927, Serial No. 217,842, and inGreat Britain September 13, 1926.

This invention comprises improvements in or relating to pulverizers. Theinvention relates to pulverizers of the type in which a beater isrotated within a casing at a very high peripheral velocity exceeding20,00()

feet per minute. Such pulverizers are sometimes known as rotarydisintegrators.

The present invention comprises in a highspeed pulverizer the provisionof an annular pulverizing zone bounded by xed internallyserrated wallsand by moving walls which carry beaters extending into the pulverizingzone.

The pulverizer may comprise in combina tion a casing having an internalannular pulverizing zone therein, an inlet thereto, an outlet therefrom,fixed serrated plates which form a lining for said pulverizing zone, arotating beater which comprises beater arms projecting into the saidpulverizing zone and means to confine materlal undergoing pulverizationwithin the limits of theV pulverizingl vvzone during the period in whichit remains within the casing.

The means to confine material undergoing pulverization within the limitsof the pulverizing zone may be constituted by the periphery of acircular boss from which the beater arms project. The construction ofthis boss as hereinafter described is a further feature of the presentinvention. v

Moreover a settling zone may be provided above the beater and incommunication with the pulverizing zone, the outlet for pulverizedmaterial being located in the upper portion Iof the settling zone.

' The interior of the casing may be lined with disintegrating membersdisposed adjacent to the operative portions of the -beater and providedwith cutting edges againstv which the material undergoing pulverizationwill be projected by the beater. The disintegrating members may compriseXed plates having on the side adjacent to the rotary 4.5 beatersharp-edged serrations.

The rotating beater may comprise a boss and beater arms projectingtherefrom which are bent forwardly in the direction of rotation toassist in projecting the material against the cutting edges, with orwlthout comprise in combination a boss concentrically mounted upon ashaft, a flange-plate secured .to the side of the boss,outwardly-extending grooves in the face of thc flange-plate or boss, orboth, beater-arms the Shanks of which lie 1n the said grooves, means todraw the Hangeplate and boss together so as to clamp the beater-armsbetween them, and lateral projections from the Shanks of the beater-arms1n co-operation with recesses in the boss or flange-plate for thepurpose of holding the beater-arms firmly in position both aganist theaction of centrifugal force and also tangential forces, while comprisinga compact construction in which the resistance to rotation isconcentrated at the beater-arms and not Wasted on useless projectionselsewhere. Two flange-plates may be provided one on either side of theboss so that two sets of beater-arms are clamped to the boss. Not onlyis the boss so constructed capable of rotation without danger atveryhigh peripheral speeds but it is easily balanced. The bolts for drawingthe flange-p1ate and boss together may be covered with cover-platesinorder to reduce the air-resistance of the boss and to prevent the entryof material undergoing pulverization into the recesses provided for thebolts. v

A machine constructed as described possesses a considerable fan-actionwhich tends to propel the material through it. If so desired thisfan-action may be supplemented by connecting the outlet to thesuction-pipe lof a suitable exhauster or fan. By such means it may beensured that any leakage due to clearance between the rotating parts andcasing is inwards rather than outwards and none of the pulverizedmaterial is lost or allowed to come into contact with the bearings ofthe machine.

An external jacket for the circulation of cooling iluidmay be providedaround the casing of the pulverizer if desired.

In the accompanying drawing which shows one form of pulverizer inaccordance with the invention Figure 1 is a side elevation with the lefthand portion in section;v

Figure -2 is a section taken on line 2-2 of Figure 1; and

Figure 3 is a detail view of a portion o f a disiiitegrating member andthe cooperating beater elements.

The pulverizer comprises a cylindrical casing having a horizontal axis.The casing is made in two parts, 11 and l2, divided horizontally and isprovided with a coolingwater jacket 13 cast in the walls of the casing.

Upon one side of the casing a feed-chute 14 for the admission ofmaterial to be disintegrated is disposed. The direction of the chute 14,is tangential to the grinding chamber 15 within the casing 11-12, and itenters it at the side thereof. The top of the casing is extendedupwardly to provide a settling zone 29 the top of which is open andprovided with a flange 16 for connection to an exit ipe. Abouttwo-thirds of the periphery o the casing 11, 12, in the lower part, islined with removable plates 17 constituting disintegrator members. Theseplates are internally serrated as shown at 18. The end walls of thecasing are likewise lined with removable serrated plates 19. The shapeof the serrations is that of a saw tooth. The length of the casing iscomparatively short in relative to its diameter. In the upper portion,which is not lined with serrated disintegrating members, the peripheral.space or settling zone 29 is spanned across its lower part adjacent tothe beater by a grating 20 of rectangular bars, the back of which opensinto the settling zone.

i' 4Within this casing there is mounted to rotate a shaft 21 whichcarries four beaterarms 22. The beater-arms are made of forged steel,and their shanks are provided at their inner ends with lateralextensions. The shanks of the arms are clamped betweenv a central discor boss 23 and two outer discs 24, 25 carried by the shaft and thelateral projections enter recesses in the central disc 23 and thusprevent the arms from flying outwards under the influence of centrifugalforce. The faces of the boss are provi ed with outwardlyextendingfgrooves 30 which receive the shanks of the beater arms 22. Thediscs are drawn together by bolts 26 the heads and nuts of which arerecessed in the discs and covered by plates 27. The discs and plates areshown in the figures with parts broken away to allow the parts behindthem to be seen. It will be noted that one pair of beater-arms pointingin opposite directions to. one another are clamped between the disc 23and disc 24 and another pair, at rightangles to the rst pair are clampedon the other side of the disc 23 by the disc 25, so that the two pairsof arms rotate in dilferent planes. The tips of thearms 22 are bentforwardly in the direction of rotation as shown by the arrow Figure 1and constitute cutting edges which face the serrations 18 and cooperatewith them. The beater-arms 22 rotate within the serrations 18 with asmall radial clearance and a slightly greater lateral clearance asshown.

It is found that a pulverizer thus con' structed is capable of dealingwith and iinely comminuting both brittle and tough materials withremarkable success. The preferred peripheral speed is 34,000 feet perminute.

1. In a high-speed disintegrator the combination of a casing theperipheral portion of which constitutes a pulverizing zone, an inletthereto, an outlet therefrom, internal impact-members within the casingin the pulverizing zone, a shaft which enters the casing, concentricallymounted clamping-plates along the shaft and beater-arms arranged instaggered relationship to one another around the shaft in balancedgroups each of which groups occupies its own plane of rotation and isheld rigidly therein between the faces of the clamping-plates.

2. A high-speed distintegrator as claimed in claim 1 wherein one of theclamping-plates constitutes a driving-boss rigidl secured upon the shaftand the remain er of the clamping-plates are symmetrically located oneach side of the driving-boss.

3. A high-speed disintegrator as claimed in claim 1 wherein the endwalls of the casing so closely approach the periphery of theconcentrically mounted clamping-plates as to constitute therewith, andwith the Vperiphery of the casing an annular pulverizing zone withinwhich the material undergoing pulverization will be confined.

4. For a high-speed disintegrator a rotating beater comprising a bossconcentrically mounted upon a shaft, a flange-plate secured to the sideof the boss, outwardly extending grooves in the face of the boss, beaterarms the shanks of which fit the said grooves, means to draw theflange-plate and boss together so as to clamp the beater arms immovablycomprising bolts and nuts, the heads of the bolts and nuts being locatedin recesses in the side of the boss and enclosed by cover plates for thepurpose described.

5. In a high-speed disintegrator, the combination of a rotatablebeater-shaft, clamping-plates mounted thereon, beater-arms having shanksheld rigidly between said clamping-plates and projecting outwardlytherefrom, bolts for drawing the clamping-plates together, the heads ofwhich are sunk in recesses in the plates, llush cover-plates overlyingsaid recesses, a pulverizer casing of which the lower portion consistsof a continuous wall to retain material to be pulverized within thecasing, which wall lies close around the path of the beater-arms,internal impact-members upon the wall, a

peripheral outwardly directed outlet from the upper part of the witlrasettling zone, and a casing in communication 1d of bars across theoutlet from the casing elow the settling 5 zone, said bars beingdisposed transversely to the direction of movement of the beaterarms.

In testimony wh saA ereof I aiiix my signature. v 'HORACE WARING.-

